Subject: [harryproa] Re: Hoyt rig
From: "jjtctaylor" <>
Date: 3/26/2008, 9:11 PM

Hoyt will never be more efficient than a marconi type sail set up. LOTS of modelling,
math, wind tunnels and a hundred years of experience says it won't be more efficient. A
UNA rig falls in the same camp. I don't think that was the inventor's intent.

It's all because the the wind slot created by the jib keeps the airflow attached on the lee
side of mainsail. It creates a coefficient of lift on the mainsail to approach 2.0. Doesn't
have be a big jib, just enough to create the flow. If the airflow separates, CL drops to .7 or
worse. When really poor the mainsail luffs. Before that have to watch the telltales.

A single sail ala Clark "Y" or other similar thin film airfoil shapes can at BEST get a
coefficient of lift of 1.2. The probability of the helmsman to get it all right is low. So we
expect 1.0 or less.

That applies to all reaches. The game changes when we are running at very broad reach to
downwind running. Spinnaker or mainsail bagging keeps the coefficient of lift to near 1.2
or even a little better, due to different ballooning effects which to date are not always well
understood. Hoyt does have a slight problem with good bagging on one tack. Seems to
run afoul with the offset mast.

What is known is low aspect rigs are more forgiving to angle of attack on all points of sail,
which keeps performance up to the practical lift limit. Makes catboat owners happy.
Higher aspect una rigs take more effort to keep shape and angle of attack in proper

All of this is a nice compare but all rigs offer a different set of compromises that have to
balance with the motivation and effort of the helm. If you aren't going fast enough, make
it bigger. Hoyt make it easier to deal with bigger??, then go for it !

My personal motivation is really really low........ so will be trying rigid wings instead.
Might find me steering with my feet, albeit dancing with the crab pots. Wing management
is a single lever, no ropes, no reef, no sound. Just GO.


--- In, "Robert" <cateran1949@...> wrote:
> -It does have an endplate that should be some improvement over the old
> split lug. I don't see why it should be less efficient than the
> ballestrom rig, and it remains balanced when reefed.
> Robert
> -- In, "proaconstrictor"
> <proaconstrictor@> wrote:
> >
> > --- In, "gunnar.westholm"
> > <gunnar.westholm@> wrote:
> > >
> > > The Balanced Rig
> > > seems stronger and more efficient then the Hoyt rig.
> >
> >
> > I doubt it's more efficient, it's just the old split lug, which wasn't
> > even more efficient than the lug with mast interference. Though Newick
> > was going to specify the split lug on one trimaran, and then it became
> > all top secret aa to why it didn't work.
> >
> >
> > > At least if the main would be fitted with a mast sleeve, like on
> > > windsurf and Wharrams Tiki rigs
> > >
> > > range/Tiki%208m%20GRP/Tiki%208m%20-%20sailing
> >
> > TIKI rigs seem to do OK and they are very easy to make since the
> > correct cut seems to be totally flat. They do have the occasional
> > reefing problem in heavy weather though.
> >
> > I think you could at least fit these rigs to proa though, whereas, I;m
> > not sure the HBR is a good condidate, though I didn't fully think og
> > that until I had posted it.
> >
> > >
> > > /Gunnar
> > >
> >

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